Surpassed only by heart disease, cancer is the second leading cause of death in the United States. Estimated by the American Cancer Society, approximately 4 million people have died from cancer since the turn of this decade. The types of cancer treatments usually include chemotherapy, surgery, radiation, hormones, and immunotherapy. Chemotherapy continues to be a powerful treatment, especially for cancers that are in inoperable or metastatic forms.
Many aryl-containing compounds have been reported to possess cytotoxic activities, e.g., 2-aryl-1,8-naphthyridin-4(1H)-ones (Chen et al., J. of Med. Chem. 1997, 40(19), 3049-56), 3-aryl-substituted oxatriazole-5-imine derivatives (Vilpo et al., Anti-Cancer Drug Design, 1997, 12(2), 75-89), and 1,2-dihydropyrido[3,4-b]pyrazines (Temple et al., J. of Med. Chem. 1987, 30(10), 1746-51).